Medical devices containing rapamycin analogs

ABSTRACT

A medical device comprises a supporting structure capable of containing or supporting a pharmaceutically acceptable carrier or excipient, which carrier or excipient may contain one or more therapeutic agents or substances, with the carrier preferably including a coating on the surface thereof, and the coating containing the therapeutic substances, such as, for example, drugs. Supporting structures for the medical devices that are suitable for use in this invention include, but are not limited to, coronary stents, peripheral stents, catheters, arterio-venous grafts, by-pass grafts, and drug delivery balloons used in the vasculature. Drugs that are suitable for use in this invention include, but are not limited to drugs of Formula (I). The drugs of Formula (I) can be used in combination with another drug including those selected from anti-proliferative agents, anti-platelet agents, anti-inflammatory agents, anti-thrombotic agents, cytotoxic drugs, agents that inhibit cytokine or chemokine binding, cell de-differentiation inhibitors, anti-lipaedemic agents, matrix metalloproteinase inhibitors, cytostatic drugs, or combinations of these drugs.

The present application is a continuation application of U.S. Ser. No.12/041,537 filed on Mar. 3, 2008, which is a divisional of U.S. Ser. No.10/488,815, filed on Mar. 5, 2004, which is a U.S. national stageapplication under 35 U.S.C. § 371 of international applicationPCT/US02/28776, filed on Sep. 10, 2002, which claims priority to U.S.Ser. No. 10/235,572, filed on Sep. 6, 2002, and U.S. Ser. No.09/950,307, filed on Sep. 10, 2001 and now U.S. Pat. No. 6,890,546. Allof the aforementioned applications are incorporated herein by referencein their entirety.

TECHNICAL FIELD

The present invention relates to novel chemical compounds havingimmunomodulatory activity and synthetic intermediates useful for thepreparation of the novel compounds, and in particular to macrolideimmunomodulators. More particularly, the invention relates tosemisynthetic analogs of rapamycin, means for their preparation,pharmaceutical compositions containing such compounds, and methods oftreatment employing the same.

BACKGROUND OF THE INVENTION

The compound cyclosporine (cyclosporin A) has found wide use since itsintroduction in the fields of organ transplantation andimmunomodulation, and has brought about a significant increase in thesuccess rate for transplantation procedures. Recently, several classesof macrocyclic compounds having potent immunomodulatory activity havebeen discovered. Okuhara et al., in European Patent Application No.184,162, published Jun. 11, 1986, disclose a number of macrocycliccompounds isolated from the genus Streptomyces, including theimmunosuppressant FK-506, a 23-membered macrocyclic lactone, which wasisolated from a strain of S. tsukubaensis.

Other related natural products, such as FR-900520 and FR-900523, whichdiffer from FK-506 in their alkyl substituent at C-21, have beenisolated from S. hygroscopicus yakushimnaensis. Another analog,FR-900525, produced by S. tsukubaensis, differs from FK-506 in thereplacement of a pipecolic acid moiety with a proline group.Unsatisfactory side-effects associated with cyclosporine and FK-506 suchas nephrotoxicity, have led to a continued search for immunosuppressantcompounds having improved efficacy and safety, including animmunosupressive agent which is effective topically, but ineffectivesystemically (U.S. Pat. No. 5,457,111).

Rapamycin is a macrocyclic triene antibiotic produced by Streptomyceshygroscopicus, which was found to have antifungal activity, particularlyagainst Candida albicans, both in vitro and in vivo (C. Vezina et al.,J. Antibiot. 1975, 28, 721; S. N. Sehgal et al., J. Antibiot. 1975, 28,727; H. A. Baker et al., J. Antibiot. 1978, 31, 539; U.S. Pat. No.3,929,992; and U.S. Pat. No. 3,993,749).

Rapamycin alone (U.S. Pat. No. 4,885,171) or in combination withpicibanil (U.S. Pat. No. 4,401,653) has been shown to have antitumoractivity. In 1977, rapamycin was also shown to be effective as animmunosuppressant in the experimental allergic encephalomyelitis model,a model for multiple sclerosis; in the adjuvant arthritis model, a modelfor rheumatoid arthritis; and was shown to effectively inhibit theformation of IgE-like antibodies (R. Martel et al., Can. J. Physiol.Pharmacol., 1977, 55, 48).

The immunosuppressive effects of rapamycin have also been disclosed inFASEB, 1989, 3, 3411 as has its ability to prolong survival time oforgan grafts in histoincompatible rodents (R. Morris, Med. Sci. Res.,1989, 17, 877). The ability of rapamycin to inhibit T-cell activationwas disclosed by M. Strauch (FASEB, 1989, 3, 3411). These and otherbiological effects of rapamycin are reviewed in Transplantation Reviews,1992, 6, 39-87.

Rapamycin has been shown to reduce neointimal proliferation in animalmodels, and to reduce the rate of restenosis in humans. Evidence hasbeen published showing that rapamycin also exhibits an anti-inflammatoryeffect, a characteristic which supported its selection as an agent forthe treatment of rheumatoid arthritis. Because both cell proliferationand inflammation are thought to be causative factors in the formation ofrestenotic lesions after balloon angioplasty and stent placement,rapamycin and analogs thereof have been proposed for the prevention ofrestenosis.

Mono-ester and di-ester derivatives of rapamycin (esterification atpositions 31 and 42) have been shown to be useful as antifungal agents(U.S. Pat. No. 4,316,885) and as water soluble prodrugs of rapamycin(U.S. Pat. No. 4,650,803).

Fermentation and purification of rapamycin and 30-demethoxy rapamycinhave been described in the literature (C. Vezina et al. J. Antibiot.(Tokyo), 1975, 28 (10), 721; S. N. Sehgal et al., J. Antibiot. (Tokyo),1975, 28(10), 727; 1983, 36(4), 351; N. L. Pavia et al., J. NaturalProducts, 1991, 54(1), 167-177).

Numerous chemical modifications of rapamycin have been attempted. Theseinclude the preparation of mono- and di-ester derivatives of rapamycin(WO 92/05179), 27-oximes of rapamycin (EPO 467606); 42-oxo analog ofrapamycin (U.S. Pat. No. 5,023,262); bicyclic rapamycins (U.S. Pat. No.5,120,725); rapamycin dimers (U.S. Pat. No. 5,120,727); silyl ethers ofrapamycin (U.S. Pat. No. 5,120,842); and aryl-sulfonates and sulfamates(U.S. Pat. No. 5,177,203). Rapamycin was recently synthesized in itsnaturally occuring enantiomeric form (K. C. Nicolaou et al., J. Am.Chem. Soc., 1993, 115, 4419-4420; S. L. Schreiber, J. Am. Chem. Soc.,1993, 115, 7906-7907; S. J. Danishefsky, J. Am. Chem. Soc., 1993, 115,9345-9346.

It has been known that rapamycin, like FK-506, binds to FKBP-12(Siekierka, J. J.; Hung, S. H. Y.; Poe, M.; Lin, C. S.; Sigal, N. H.,Nature, 1989, 341, 755-757; Harding, M. W.; Galat, A.; Uehling, D. E.;Schreiber, S. L., Nature, 1989, 341, 758-760; Dumont, F. J.; Melino, M.R.; Staruch, M. J.; Koprak, S. L.; Fischer, P. A.; Sigal, N. H., J.Immunol., 1990, 144, 1418-1424; Bierer, B. E.; Schreiber, S. L.;Burakoff, S. J., Eur. J. Immunol., 1991, 21, 439-445; Fretz, H.; Albers,M. W.; Galat, A.; Standaert, R. F.; Lane, W. S.; Burakoff, S. J.;Bierer, B. E.; Schreiber, S. L., J. Am. Chem. Soc., 1991, 113,1409-1411). Recently it has been discovered that the rapamycin/FKBP-12complex binds to yet another protein, which is distinct fromcalcineurin, the protein that the FK-506/FKBP-12 complex inhibits(Brown, E. J.; Albers, M. W.; Shin, T. B.; Ichikawa, K.; Keith, C. T.;Lane, W. S.; Schreiber, S. L., Nature, 1994, 369, 756-758; Sabatini, D.M.; Erdjument-Bromage, H.; Lui, M.; Tempest, P.; Snyder, S. H., Cell,1994, 78, 35-43).

Percutaneous transluminal coronary angioplasty (PTCA) was developed byAndreas Gruntzig in the 1970's. The first canine coronary dilation wasperformed on Sep. 24, 1975; studies showing the use of PTCA werepresented at the annual meetings of the American Heart Association thefollowing year. Shortly thereafter, the first human patient was studiedin Zurich, Switzerland, followed by the first American human patients inSan Francisco and New York. While this procedure changed the practice ofinterventional cardiology with respect to treatment of patients withobstructive coronary artery disease, the procedure did not providelong-term solutions. Patients received only temporary abatement of thechest pain associated with vascular occlusion; repeat procedures wereoften necessary. It was determined that the existence of restenoticlesions severely limited the usefulness of the new procedure. In thelate 1980's, stents were introduced to maintain vessel patency afterangioplasty. Stenting is involved in 90% of angioplasty performed today.Before the introduction of stents, the rate of restenosis ranged from30% to 50% of the patients who were treated with balloon angioplasty.The recurrence rate after dilatation of in-stent restenosis may be ashigh as 70% in selected patient subsets, while the angiographicrestenosis rate in de novo stent placement is about 20%. Placement ofthe stent reduced the restenosis rate to 15% to 20%. This percentagelikely represents the best results obtainable with purely mechanicalstenting. The restenosis lesion is caused primarily by neointimalhyperplasia, which is distinctly different from atherosclerotic diseaseboth in time-course and in histopathologic appearance. Restenosis is ahealing process of damaged coronary arterial walls, with neointimaltissue impinging significantly on the vessel lumen. Vascularbrachytherapy appears to be efficacious against in-stent restenosislesions. Radiation, however, has limitations of practicality andexpense, and lingering questions about safety and durability.

Accordingly, it is desired to reduce the rate of restenosis by at least50% of its current level. It is for this reason that a major effort isunderway by the interventional device community to fabricate andevaluate drug-eluting stents. Such devices could have many advantages ifthey were successful, principally since such systems would need noauxiliary therapies, either in the form of peri-procedural techniques orchronic oral pharmacotherapy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows blood concentrations ±SEM (n=3) of tetrazole-containingrapamycin analogs dosed in monkey.

FIG. 2 is a side view in elevation showing a stent suitable for use inthis invention.

FIG. 3A is a cross-sectional view of a vessel segment in which wasplaced a stent coated with a polymer only.

FIG. 3B is a cross-sectional view of a vessel segment in which wasplaced a stent coated with a polymer plus drug.

SUMMARY OF THE INVENTION

In one aspect of the present invention are disclosed compoundsrepresented by the structural formula:

or a pharmaceutically acceptable salt or prodrug thereof.

Another object of the present invention is to provide syntheticprocesses for the preparation of such compounds from starting materialsobtained by fermentation, as well as chemical intermediates useful insuch synthetic processes.

A further object of the invention is to provide pharmaceuticalcompositions containing, as an active ingredient, at least one of theabove compounds.

Yet another object of the invention is to provide a method of treating avariety of disease states, including restenosis, post-transplant tissuerejection, immune and autoimmune dysfunction, fungal growth, and cancer.

In another aspect this invention provides a medical device comprising asupporting structure having a coating on the surface thereof, thecoating containing a therapeutic substance, such as, for example, adrug. Supporting structures for the medical devices that are suitablefor use in this invention include, but are not limited to, coronarystents, peripheral stents, catheters, arterio-venous grafts, by-passgrafts, and drug delivery balloons used in the vasculature. Drugs thatare suitable for use in this invention include, but are not limited to,

or a pharmaceutically acceptable salt or prodrug thereof, which includes

or a pharmaceutically acceptable salt or prodrug thereof (hereinafteralternatively referred to as A-179578, or ABT-578), and

or a pharmaceutically acceptable salt or prodrug thereof;

or a pharmaceutically acceptable salt or prodrug thereof (hereinafteralternatively referred to as SDZ RAD or40-O-(2-hydroxyethyl)-rapamycin);

or a pharmaceutically acceptable salt or prodrug thereof (hereinafteralternatively referred to as A-94507).

Coatings that are suitable for use in this invention include, but arenot limited to, polymeric coatings that can comprise any polymericmaterial in which the therapeutic agent, i.e., the drug, issubstantially soluble. The coating can be hydrophilic, hydrophobic,biodegradable, or non-biodegradable. This medical device reducesrestenosis in vasculature. The direct coronary delivery of a drug suchas A-179578 is expected to reduce the rate of restenosis to a level ofabout 0% to 25%.

DETAILED DESCRIPTION OF THE INVENTION

Definition of Terms

The term “prodrug,” as used herein, refers to compounds which arerapidly transformed in vivo to the parent compound of the above formula,for example, by hydrolysis in blood. A thorough discussion is providedby T. Higuchi and V. Stella, “Prodrugs as Novel Delivery systems,” Vol.14 of the A.C.S. Symposium Series, and in Edward B. Roche, ed.,“Bioreversible Carriers in Drug Design,” American PharmaceuticalAssociation and Pergamon Press, 1987, both of which are incorporatedherein by reference.

The term “pharmaceutically acceptable prodrugs”, as used herein, refersto those prodrugs of the compounds of the present invention which are,within the scope of sound medical judgment, suitable for use in contactwith the tissues of humans and lower mammals without undue toxicity,irritation, and allergic response, are commensurate with a reasonablebenefit/risk ratio, and are effective for their intended use, as well asthe zwitterionic forms, where possible, of the compounds of theinvention. Particularly preferred pharmaceutically acceptable prodrugsof this invention are prodrug esters of the C-31 hydroxyl group ofcompounds of this invention.

The term “prodrug esters,” as used herein, refers to any of severalester-forming groups that are hydrolyzed under physiological conditions.Examples of prodrug ester groups include acetyl, ethanoyl, pivaloyl,pivaloyloxymethyl, acetoxymethyl, phthalidyl, methoxymethyl, indanyl,and the like, as well as ester groups derived from the coupling ofnaturally or unnaturally occurring amino acids to the C-31 hydroxylgroup of compounds of this invention.

The term “supporting structure” means a framework that is capable ofcontaining or supporting a pharmaceutically acceptable carrier orexcipient, which carrier or excipient may contain one or moretherapeutic agents or substances, e.g., one or more drugs and/or othercompounds. The supporting structure is typically formed of metal or apolymeric material. Suitable supporting structures formed of polymericmaterials, including biodegradable polymers, capable of containing thetherapeutic agents or substances include, without limitation, thosedisclosed in U.S. Pat. Nos. 6,413,272 and 5,527,337, which areincorporated herein by reference.

EMBODIMENTS

In one embodiment of the invention is a compound of formula

In another embodiment of the invention is a compound of formula

Preparation of Compounds of this Invention

The compounds and processes of the present invention will be betterunderstood in connection with the following synthetic schemes whichillustrate the methods by which the compounds of the invention may beprepared.

The compounds of this invention may be prepared by a variety ofsynthetic routes. A representative procedure is shown in Scheme 1.

As shown in Scheme 1, conversion of the C-42 hydroxyl of rapamycin to atrifluoromethanesulfonate or fluorosulfonate leaving group providedcompound A. Displacement of the leaving group with tetrazole in thepresence of a hindered, non-nucleophilic base, such as 2,6-lutidine, or,preferably, diisopropylethyl amine provided isomers B and C, which wereseparated and purified by flash column chromatography.

Synthetic Methods

The foregoing may be better understood by reference to the followingexamples which illustrate the methods by which the compounds of theinvention may be prepared and are not intended to limit the scope of theinvention as defined in the appended claims.

Example 1 42-Epi-(tetrazolyl)-rapamycin (Less Polar Isomer) Example 1A

A solution of rapamycin (100 mg, 0.11 mmol) in dichloromethane (0.6 mL)at −78° C. under a nitrogen atmosphere was treated sequentially with2,6-lutidine (53 uL, 0.46 mmol, 4.3 eq.) and trifluoromethanesulfonicanhydride (37 uL, 0.22 mmol), and stirred thereafter for 15 minutes,warmed to room temperature and eluted through a pad of silica gel (6 mL)with diethyl ether. Fractions containing the triflate were pooled andconcentrated to provide the designated compound as an amber foam.

Example 1B 42-Epi-(tetrazolyl)-rapamycin (Less Polar Isomer)

A solution of the triflate compound from Example 1A in isopropyl acetate(0.3 mL) was treated sequentially with diisopropylethylamine (87 uL, 0.5mmol) and 1H-tetrazole (35 mg, 0.5 mmol), and thereafter stirred for 18hours. This mixture was partitioned between water (10 mL) and ether (10mL). The organics were washed with brine (10 mL) and dried (Na₂SO₄).Concentration of the organics provided a sticky yellow solid which waspurified by chromatography on silica gel (3.5 g, 70-230 mesh) elutingwith hexane (10 mL), hexane:ether (4:1 (10 mL), 3:1 (10 mL), 2:1 (10mL), 1:1 (10 mL)), ether (30 mL), hexane:acetone (1:1 (30 mL)). One ofthe isomers was collected in the ether fractions. MS (ESI) m/e 966 (M)⁻.

Example 2 42-Epi-(tetrazolyl)-rapamycin (More Polar Isomer)

Collection of the slower moving band from the chromatography columnusing the hexane:acetone (1:1) mobile phase in Example 1B provided thedesignated compound. MS (ESI) m/e 966 (M)⁻.

In Vitro Assay of Biological Activity

The immunosuppressant activity of the compounds of the present inventionwas compared to rapamycin and two rapamycin analogs:40-epi-N-[2′-pyridone]-rapamycin and 40-epi-N-[4′-pyridone]-rapamycin,both disclosed in U.S. Pat. No. 5,527,907. The activity was determinedusing the human mixed lymphocyte reaction (MLR) assay described by Kino,T. et al. in Transplantation Proceedings, XIX (5): 36-39, Suppl. 6(1987). The results of the assay demonstrate that the compounds of theinvention are effective immunomodulators at nanomolar concentrations, asshown in Table 1.

TABLE 1 Human MLR Example IC₅₀ ± S.E.M. (nM) Rapamycin 0.91 ± 0.362-pyridone 12.39 ± 5.3  4-pyridone 0.43 ± 0.20 Example 1 1.70 ± 0.48Example 2 0.66 ± 0.19

The pharmacokinetic behaviors of the Example 1 and Example 2 compoundswere characterized following a single 2.5 mg/kg intravenous dose incynomolgus monkey (n=3 per group). Each compound was prepared as 2.5mg/mL solution in a 20% ethanol:30% propylene glycol:2% cremophor EL:48%dextrose:5% in water vehicle.

The 1 mL/kg intravenous dose was administered as a slow bolus (about 1-2minutes) in a saphenous vein of the monkeys. Blood samples were obtainedfrom a femoral artery or vein of each animal prior to dosing and 0.1 (IVonly), 0.25, 0.5, 1, 1.5, 2, 4, 6, 9, 12, 24, and 30 hours after dosing.The EDTA preserved samples were thoroughly mixed and extracted forsubsequent analysis.

An aliquot of blood (1.0 mL) was hemolyzed with 20% methanol in water(0.5 ml) containing an internal standard. The hemolyzed samples wereextracted with a mixture of ethyl acetate and hexane (1:1 (v/v), 6.0mL). The organic layer was evaporated to dryness with a stream ofnitrogen at room temperature. Samples were reconstituted inmethanol:water (1:1, 150 uL). The title compounds (50 uL injection) wereseparated from contaminants using reverse phase HPLC with UV detection.Samples were kept cool (4° C.) through the run. All samples from eachstudy were analyzed as a single batch on the HPLC.

Area under the curve (AUC) measurements of Example 1, Example 2 and theinternal standard were determined using the Sciex MacQuan™ software.Calibration curves were derived from peak area ratio (parentdrug/internal standard) of the spiked blood standards using leastsquares linear regression of the ratio versus the theoreticalconcentration. The methods were linear for both compounds over the rangeof the standard curve (correlation >0.99) with an estimated quantitationlimit of 0.1 The maximum blood concentration (C_(MAX)) and the time toreach the maximum blood concentration ng/mL. (T_(MAX)) were readdirectly from the observed blood concentration-time data. The bloodconcentration data were submitted to multi-exponential curve fittingusing CSTRIP to obtain estimates of pharmacokinetic parameters. Theestimated parameters were further defined using NONLIN84. The area underthe blood concentration-time curve from 0 to t hours (last measurableblood concentration time point) after dosing (AUC_(0-t)) was calculatedusing the linear trapezoidal rule for the blood-time profiles. Theresidual area extrapolated to infinity, determined as the final measuredblood concentration (C_(t)) divided by the terminal elimination rateconstant (β), and added to AUC_(0-t) to produce the total area under thecurve (AUC_(0-t)).

As shown in FIG. 1 and Table 2, both Example 1 and Example 2 compoundshad a surprisingly substantially shorter terminal elimination half-life(t_(1/2)) when compared to rapamycin. Thus, only the compounds of theinvention provide both sufficient efficacy (Table 1) and a shorterterminal half-life (Table 2).

TABLE 2 AUC t_(1/2) Compound ng · hr/mL (hours) Rapamycin 6.87 16.72-pyridone 2.55 2.8 4-pyridone 5.59 13.3 Example 1 2.35 5.0 Example 22.38 6.9

Methods of Treatment

The compounds of the invention, including but not limited to thosespecified in the examples, possess immunomodulatory activity in mammals(especially humans). As immunosuppressants, the compounds of the presentinvention are useful for the treatment and prevention of immune-mediateddiseases such as the resistance by transplantation of organs or tissuessuch as heart, kidney, liver, medulla ossium, skin, cornea, lung,pancreas, intestinum tenue, limb, muscle, nerves, duodenum, small-bowel,pancreatic-islet-cell, and the like; graft-versus-host diseases broughtabout by medulla ossium transplantation; autoimmune diseases such asrheumatoid arthritis, systemic lupus erythematosus, Hashimoto'sthyroiditis, multiple sclerosis, myasthenia gravis, type I diabetes,uveitis, allergic encephalomyelitis, glomerulonephritis, and the like.Further uses include the treatment and prophylaxis of inflammatory andhyperproliferative skin diseases and cutaneous manifestations ofimmunologically-mediated illnesses, such as psoriasis, atopicdermatitis, contact dermatitis and further eczematous dermatitises,seborrhoeis dermatitis, lichen planus, pemphigus, bullous pemphigoid,epidermolysis bullosa, urticaria, angioedemas, vasculitides, erythemas,cutaneous eosinophilias, lupus erythematosus, acne and alopecia areata;various eye diseases (autoimmune and otherwise) such askeratoconjunctivitis, vernal conjunctivitis, uveitis associated withBehcet's disease, keratitis, herpetic keratitis, conical cornea,dystrophia epithelialis corneae, corneal leukoma, and ocular pemphigus.In addition reversible obstructive airway diseases, which includeconditions such as asthma (for example, bronchial asthma, allergicasthma, intrinsic asthma, extrinsic asthma and dust asthma),particularly chronic or inveterate asthma (for example, late asthma andairway hyper-responsiveness), bronchitis, allergic rhinitis, and thelike are targeted by compounds of this invention. Inflammation of mucosaand blood vessels such as gastric ulcers, vascular damage caused byischemic diseases and thrombosis, and hyperproliferative vasculardiseases such as intimal smooth muscle cell hyperplasia, restenosis andvascular occlusion, particularly following biologically- ormechanically-mediated vascular injury, could also be treated orprevented by the compounds of the invention.

The compounds or drugs described herein can be applied to stents thathave been coated with a polymeric compound. Incorporation of thecompound or drug into the polymeric coating of the stent can be carriedout by dipping the polymer-coated stent into a solution containing thecompound or drug for a sufficient period of time (such as, for example,five minutes) and then drying the coated stent, preferably by means ofair drying for a sufficient period of time (such as, for example, 30minutes). The polymer-coated stent containing the compound or drug canthen be delivered to the coronary vessel by deployment from a ballooncatheter. In addition to stents, other devices that can be used tointroduce the drugs of this invention to the vasculature include, butare not limited to grafts, catheters, and balloons. In addition, othercompounds or drugs that can be used in lieu of the drugs of thisinvention include, but are not limited to, A-94507 and SDZ RAD.

The compounds described herein for use in polymer-coated stents can beused in combination with other pharmacological agents. Thepharmacological agents that would, in combination with the compounds ofthis invention, be most effective in preventing restenosis can beclassified into the categories of anti-proliferative agents,anti-platelet agents, anti-inflammatory agents, anti-thrombotic agents,and thrombolytic agents. These classes can be further sub-divided. Forexample, anti-proliferative agents can be anti-mitotic. Anti-mitoticagents inhibit or affect cell division, whereby processes normallyinvolved in cell division do not take place. One sub-class ofanti-mitotic agents includes vinca alkaloids. Representative examples ofvinca alkaloids include, but are not limited to, vincristine,paclitaxel, etoposide, nocodazole, indirubin, and anthracyclinederivatives, such as, for example, daunorubicin, daunomycin, andplicamycin. Other sub-classes of anti-mitotic agents includeanti-mitotic alkylating agents, such as, for example, tauromustine,bofumustine, and fotemustine, and anti-mitotic metabolites, such as, forexample, methotrexate, fluorouracil, 5-bromodeoxyuridine, 6-azacytidine,and cytarabine. Anti-mitotic alkylating agents affect cell division bycovalently modifying DNA, RNA, or proteins, thereby inhibiting DNAreplication, RNA transcription, RNA translation, protein synthesis, orcombinations of the foregoing.

Anti-platelet agents are therapeutic entities that act by (1) inhibitingadhesion of platelets to a surface, typically a thrombogenic surface,(2) inhibiting aggregation of platelets, (3) inhibiting activation ofplatelets, or (4) combinations of the foregoing. Activation of plateletsis a process whereby platelets are converted from a quiescent, restingstate to one in which platelets undergo a number of morphologic changesinduced by contact with a thrombogenic surface. These changes includechanges in the shape of the platelets, accompanied by the formation ofpseudopods, binding to membrane receptors, and secretion of smallmolecules and proteins, such as, for example, ADP and platelet factor 4.Anti-platelet agents that act as inhibitors of adhesion of plateletsinclude, but are not limited to, eptifibatide, tirofiban, RGD(Arg-Gly-Asp)-based peptides that inhibit binding to gpIIbIIIa or αvβ3,antibodies that block binding to gpIIaIIIb or αvβ3, anti-P-selectinantibodies, anti-E-selectin antibodies, peptides that block P-selectinor E-selectin binding to their respective ligands, saratin, and anti-vonWillebrand factor antibodies. Agents that inhibit ADP-mediated plateletaggregation include, but are not limited to, disagregin and cilostazol.

Anti-inflammatory agents can also be used. Examples of these include,but are not limited to, prednisone, dexamethasone, hydrocortisone,estradiol, and non-steroidal anti-inflammatories, such as, for example,acetaminophen, ibuprofen, naproxen, and sulindac. Other examples ofthese agents include those that inhibit binding of cytokines orchemokines to the cognate receptors to inhibit pro-inflammatory signalstransduced by the cytokines or the chemokines. Representative examplesof these agents include, but are not limited to, anti-IL1, anti-IL2,anti-IL3, anti-IL4, anti-IL8, anti-IL15, anti-GM-CSF, and anti-TNFantibodies.

Anti-thrombotic agents include chemical and biological entities that canintervene at any stage in the coagulation pathway. Examples of specificentities include, but are not limited to, small molecules that inhibitthe activity of factor Xa. In addition, anti-thrombotic agents includeheparinoid-type agents that can inhibit both FXa and thrombin, eitherdirectly or indirectly, such as, for example, heparin, heparan sulfate,low molecular weight heparins, such as, for example, the compound havingthe trademark Clivarin®, and synthetic oligosaccharides, such as, forexample, the compound having the trademark Arixtra®. Anti-thromboticagents also include direct thrombin inhibitors, such as, for example,melagatran, ximelagatran, argatroban, inogatran, and peptidomimetics ofbinding site of the Phe-Pro-Arg fibrinogen substrate for thrombin.Another class of anti-thrombotic agents that can be delivered are factorVII/VIIa inhibitors, such as, for example, anti-factor VII/VIIaantibodies, rNAPc2, and tissue factor pathway inhibitor (TFPI).

Thrombolytic agents, which may be defined as agents that help degradethrombi (clots), can also be used as adjunctive agents, because theaction of lysing a clot helps to disperse platelets trapped within thefibrin matrix of a thrombus. Representative examples of thrombolyticagents include, but are not limited to, urokinase or recombinanturokinase, pro-urokinase or recombinant pro-urokinase, tissueplasminogen activator or its recombinant form, and streptokinase.

Other drugs that can be used in combination with the compounds of thisinvention are cytotoxic drugs, such as, for example, apoptosis inducers,such as TGF, and topoisomerase inhibitors, such as,10-hydroxycamptothecin, irinotecan, and doxorubicin. Other classes ofdrugs that can be used in combination with the compounds of thisinvention are drugs that inhibit cell de-differentiation and cytostaticdrugs.

Other agents that can be used in combination with the compounds of thisinvention include anti-lipaedemic agents such as, for example,fenofibrate, matrix metalloproteinase inhibitors such as, for example,batimistat, antagonists of the endothelin-A receptor such as, forexample, darusentan, and antagonists of the α_(v)β₃ integrin receptor.

When used in the present invention, the coating can comprise anypolymeric material in which the therapeutic agent, i.e., the drug, issubstantially soluble. The purpose of the coating is to serve as acontrolled release vehicle for the therapeutic agent or as a reservoirfor a therapeutic agent to be delivered at the site of a lesion. Thecoating can be polymeric and can further be hydrophilic, hydrophobic,biodegradable, or non-biodegradable. The material for the polymericcoating can be selected from the group consisting of polycarboxylicacids, cellulosic polymers, gelatin, polyvinylpyrrolidone, maleicanhydride polymers, polyamides, polyvinyl alcohols, polyethylene oxides,glycosaminoglycans, polysaccharides, polyesters, polyurethanes,silicones, polyorthoesters, polyanhydrides, polycarbonates,polypropylenes, polylactic acids, polyglycolic acids, polycaprolactones,polyhydroxybutyrate valerates, polyacrylamides, polyethers, and mixturesand copolymers of the foregoing. Coatings prepared from polymericdispersions such as polyurethane dispersions (BAYHYDROL, etc.) andacrylic acid latex dispersions can also be used with the therapeuticagents of the present invention.

Biodegradable polymers that can be used in this invention includepolymers such as poly(L-lactic acid), poly(DL-lactic acid),polycaprolactone, poly(hydroxy butyrate), polyglycolide,poly(dioxanone), poly(hydroxy valerate), polyorthoester; copolymers suchas poly(lactide-co-glycolide), polyhydroxy(butyrate-co-valerate),polyglycolide-co-trimethylene carbonate; polyanhydrides;polyphosphoesters; polyphosphoesterurethanes; polyamino acids;polycyanoacrylates; biomolecules such as fibrin, fibrinogen, cellulose,starch, collagen and hyaluronic acid; and mixtures of the foregoing.Biostable materials that are suitable for use in this invention includepolymers such as polyurethanes, silicones, polyesters, polyolefins,polyamides, polycaprolactam, polyimides, polyvinyl chloride, polyvinylmethyl ether, polyvinyl alcohol, acrylic polymers and copolymers,polyacrylonitrile, polystyrene copolymers of vinyl monomers with olefins(such as styrene acrylonitrile copolymers, ethylene methyl methacrylatecopolymers, ethylene vinyl acetate), polyethers, rayons, cellulosics(such as cellulose acetate, cellulose nitrate, cellulose propionate,etc.), parylene and derivatives thereof; and mixtures and copolymers ofthe foregoing.

Another polymer that can be used in this invention ispoly(MPC_(w):LAM_(x):HPMA_(y):TSMA_(z)) where w, x, y, and z representthe molar ratios of monomers used in the feed for preparing the polymerand MPC represents the unit 2-methacryoyloxyethylphosphorylcholine, LMArepresents the unit lauryl methacrylate, HPMA represents the unit2-hydroxypropyl methacrylate, and TSMA represents the unit3-trimethoxysilylpropyl methacrylate. The drug-impregnated stent can beused to maintain patency of a coronary artery previously occluded bythrombus and/or atherosclerotic plaque. The delivery of ananti-proliferative agent reduces the rate of in-stent restenosis.

Other treatable conditions include but are not limited to ischemic boweldiseases, inflammatory bowel diseases, necrotizing enterocolitis,intestinal inflammations/allergies such as Coeliac diseases, proctitis,eosinophilic gastroenteritis, mastocytosis, Crohn's disease andulcerative colitis; nervous diseases such as multiple myositis,Guillain-Barre syndrome, Meniere's disease, polyneuritis, multipleneuritis, mononeuritis and radiculopathy; endocrine diseases such ashyperthyroidism and Basedow's disease; hematic diseases such as pure redcell aplasia, aplastic anemia, hypoplastic anemia, idiopathicthrombocytopenic purpura, autoimmune hemolytic anemia, agranulocytosis,pernicious anemia, megaloblastic anemia and anerythroplasia; bonediseases such as osteoporosis; respiratory diseases such as sarcoidosis,fibroid lung and idiopathic interstitial pneumonia; skin disease such asdermatomyositis, leukoderma vulgaris, ichthyosis vulgaris, photoallergicsensitivity and cutaneous T cell lymphoma; circulatory diseases such asarteriosclerosis, atherosclerosis, aortitis syndrome, polyarteritisnodosa and myocardosis; collagen diseases such as scleroderma, Wegener'sgranuloma and Sjogren's syndrome; adiposis; eosinophilic fasciitis;periodontal disease such as lesions of gingiva, periodontium, alveolarbone and substantia ossea dentis; nephrotic syndrome such asglomerulonephritis; male pattern aleopecia or alopecia senilis bypreventing epilation or providing hair germination and/or promoting hairgeneration and hair growth; muscular dystrophy; Pyoderma and Sezary'ssyndrome; Addison's disease; active oxygen-mediated diseases, as forexample organ injury such as ischemia-reperfusion injury of organs (suchas heart, liver, kidney and digestive tract) which occurs uponpreservation, transplantation or ischemic disease (for example,thrombosis and cardiac infarction); intestinal diseases such asendotoxin-shock, pseudomembranous colitis and colitis caused by drug orradiation; renal diseases such as ischemic acute renal insufficiency andchronic renal insufficiency; pulmonary diseases such as toxinosis causedby lung-oxygen or drug (for example, paracort and bleomycins), lungcancer and pulmonary emphysema; ocular diseases such as cataracta,siderosis, retinitis, pigmentosa, senile macular degeneration, vitrealscarring and corneal alkali burn; dermatitis such as erythemamultiforme, linear IgA ballous dermatitis and cement dermatitis; andothers such as gingivitis, periodontitis, sepsis, pancreatitis, diseasescaused by environmental pollution (for example, air pollution), aging,carcinogenesis, metastasis of carcinoma and hypobaropathy; diseasescaused by histamine or leukotriene-C₄ release; Behcet's disease such asintestinal-, vasculo- or neuro-Behcet's disease, and also Behcet's whichaffects the oral cavity, skin, eye, vulva, articulation, epididymis,lung, kidney and so on. Furthermore, the compounds of the invention areuseful for the treatment and prevention of hepatic disease such asimmunogenic diseases (for example, chronic autoimmune liver diseasessuch as autoimmune hepatitis, primary biliary cirrhosis and sclerosingcholangitis), partial liver resection, acute liver necrosis (e.g.necrosis caused by toxin, viral hepatitis, shock or anoxia), B-virushepatitis, non-A/non-B hepatitis, cirrhosis (such as alcoholiccirrhosis) and hepatic failure such as fulminant hepatic failure,late-onset hepatic failure and “acute-on-chronic” liver failure (acuteliver failure on chronic liver diseases), and moreover are useful forvarious diseases because of their useful activity such as augmention ofchemotherapeutic effect, cytomegalovirus infection, particularly HCMVinfection, anti-inflammatory activity, sclerosing and fibrotic diseasessuch as nephrosis, scleroderma, pulmonary fibrosis, arteriosclerosis,congestive heart failure, ventricular hypertrophy, post-surgicaladhesions and scarring, stroke, myocardial infarction and injuryassociated with ischemia and reperfusion, and the like.

Additionally, compounds of the invention possess FK-506 antagonisticproperties. The compounds of the present invention may thus be used inthe treatment of immunodepression or a disorder involvingimmunodepression. Examples of disorders involving immunodepressioninclude AIDS, cancer, fungal infections, senile dementia, trauma(including wound healing, surgery and shock) chronic bacterialinfection, and certain central nervous system disorders. Theimmunodepression to be treated may be caused by an overdose of animmunosuppressive macrocyclic compound, for example derivatives of12-(2-cyclohexyl-1-methylvinyl)-13,19,21,27-tetramethyl-11,28-dioxa-4-azatricyclo[22.3.1.0^(4,9)]octacos-18-enesuch as FK-506 or rapamycin. The overdosing of such medicants bypatients is quite common upon their realizing that they have forgottento take their medication at the prescribed time and can lead to seriousside effects.

The ability of the compounds of the invention to treat proliferativediseases can be demonstrated according to the methods described in E. T.Bunchman and C. A. Brookshire, Transplantation Proceed., 23, 967-968(1991); Yamagishi et al., Biochem. Biophys. Res. Comm., 191, 840-846(1993); and Shichiri et al., J. Clin. Invest., 87, 1867-1871 (1991).Proliferative diseases include smooth muscle proliferation, systemicsclerosis, cirrhosis of the liver, adult respiratory distress syndrome,idiopathic cardiomyopathy, lupus erythematosus, diabetic retinopathy orother retinopathies, psoriasis, scleroderma, prostatic hyperplasia,cardiac hyperplasia, restenosis following arterial injury or otherpathologic stenosis of blood vessels. In addition, these compoundsantagonize cellular responses to several growth factors, and thereforepossess antiangiogenic properties, making them useful agents to controlor reverse the growth of certain tumors, as well as fibrotic diseases ofthe lung, liver, and kidney.

Aqueous liquid compositions of the present invention are particularlyuseful for the treatment and prevention of various diseases of the eyesuch as autoimmune diseases (including, for example, conical cornea,keratitis, dysophia epithelialis corneae, leukoma, Mooren's ulcer,sclevitis and Graves' ophthalmopathy) and rejection of cornealtransplantation.

When used in the above or other treatments, a therapeutically effectiveamount of one of the compounds of the present invention may be employedin pure form or, where such forms exist, in pharmaceutically acceptablesalt, ester or prodrug form. Alternatively, the compound may beadministered as a pharmaceutical composition containing the compound ofinterest in combination with one or more pharmaceutically acceptableexcipients. The phrase “therapeutically effective amount” of thecompound of the invention means a sufficient amount of the compound totreat disorders, at a reasonable benefit/risk ratio applicable to anymedical treatment. It will be understood, however, that the total dailyusage of the compounds and compositions of the present invention will bedecided by the attending physician within the scope of sound medicaljudgement. The specific therapeutically effective dose level for anyparticular patient will depend upon a variety of factors including thedisorder being treated and the severity of the disorder; activity of thespecific compound employed; the specific composition employed; the age,body weight, general health, sex and diet of the patient; the time ofadministration, route of administration, and rate of excretion of thespecific compound employed; the duration of the treatment; drugs used incombination or coincidental with the specific compound employed; andlike factors well known in the medical arts. For example, it is wellwithin the skill of the art to start doses of the compound at levelslower than required to achieve the desired therapeutic effect and togradually increase the dosage until the desired effect is achieved.

The total daily dose of the compounds of this invention administered toa human or lower animal may range from about 0.01 to about 10 mg/kg/day.For purposes of oral administration, more preferable doses may be in therange of from about 0.001 to about 3 mg/kg/day. For the purposes oflocal delivery from a stent, the daily dose that a patient will receivedepends on the length of the stent. For example, a 15 mm coronary stentmay contain a drug in an amount ranging from about 1 to about 120micrograms and may deliver that drug over a time period ranging fromseveral hours to several weeks. If desired, the effective daily dose maybe divided into multiple doses for purposes of administration;consequently, single dose compositions may contain such amounts orsub-multiples thereof to make up the daily dose. Topical administrationmay involve doses ranging from 0.001 to 3% mg/kg/day, depending on thesite of application.

Pharmaceutical Compositions

The pharmaceutical compositions of the present invention comprise acompound of the invention and a pharmaceutically acceptable carrier orexcipient, which may be administered orally, rectally, parenterally,intracisternally, intravaginally, intraperitoneally, topically (as bypowders, ointments, drops or transdermal patch), bucally, as an oral ornasal spray, or locally, as in a stent placed within the vasculature.The phrase “pharmaceutically acceptable carrier” means a non-toxicsolid, semi-solid or liquid filler, diluent, encapsulating material orformulation auxiliary of any type. The term “parenteral,” as usedherein, refers to modes of administration which include intravenous,intraarterial, intramuscular, intraperitoneal, intrasternal,subcutaneous and intraarticular injection, infusion, and placement, suchas, for example, in vasculature.

Pharmaceutical compositions of this invention for parenteral injectioncomprise pharmaceutically acceptable sterile aqueous or nonaqueoussolutions, dispersions, suspensions or emulsions as well as sterilepowders for reconstitution into sterile injectable solutions ordispersions just prior to use. Examples of suitable aqueous andnonaqueous carriers, diluents, solvents or vehicles include water,ethanol, polyols (such as glycerol, propylene glycol, polyethyleneglycol, and the like), carboxymethylcellulose and suitable mixturesthereof, vegetable oils (such as olive oil), and injectable organicesters such as ethyl oleate. Proper fluidity can be maintained, forexample, by the use of coating materials such as lecithin, by themaintenance of the required particle size in the case of dispersions,and by the use of surfactants.

These compositions may also contain adjuvants such as preservatives,wetting agents, emulsifying agents, and dispersing agents. Prevention ofthe action of microorganisms may be ensured by the inclusion of variousantibacterial and antifungal agents, for example, paraben,chlorobutanol, phenol sorbic acid, and the like. It may also bedesirable to include isotonic agents such as sugars, sodium chloride,and the like. Prolonged absorption of the injectable pharmaceutical formmay be brought about by the inclusion of agents that delay absorptionsuch as aluminum monostearate and gelatin.

In some cases, in order to prolong the effect of the drug, it isdesirable to slow the absorption of the drug from subcutaneous orintramuscular injection. This may be accomplished by the use of a liquidsuspension of crystalline or amorphous material with poor watersolubility. The rate of absorption of the drug then depends upon itsrate of dissolution which, in turn, may depend upon crystal size andcrystalline form. Alternatively, delayed absorption of a parenterallyadministered drug form is accomplished by dissolving or suspending thedrug in an oil vehicle.

Injectable depot forms are made by forming microencapsule matrices ofthe drug in biodegradable polymers such as polylactide-polyglycolide.Depending upon the ratio of drug to polymer and the nature of theparticular polymer employed, the rate of drug release can be controlled.Examples of other biodegradable polymers include poly(orthoesters) andpoly(anhydrides). Depot injectable formulations are also prepared byentrapping the drug in liposomes or microemulsions which are compatiblewith body tissues.

The injectable formulations can be sterilized, for example, byfiltration through a bacterial-retaining filter, or by incorporatingsterilizing agents in the form of sterile solid compositions which canbe dissolved or dispersed in sterile water or other sterile injectablemedium just prior to use.

Solid dosage forms for oral administration include capsules, tablets,pills, powders, and granules. In such solid dosage forms, the activecompound is mixed with at least one inert, pharmaceutically acceptableexcipient or carrier such as sodium citrate or dicalcium phosphateand/or a) fillers or extenders such as starches, lactose, sucrose,glucose, mannitol, and silicic acid, b) binders such as, for example,carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidone,sucrose, and acacia, c) humectants such as glycerol, d) disintegratingagents such as agar-agar, calcium carbonate, potato or tapioca starch,alginic acid, certain silicates, and sodium carbonate, e) solutionretarding agents such as paraffin, f) absorption accelerators such asquaternary ammonium compounds, g) wetting agents such as, for example,cetyl alcohol and glycerol monostearate, h) absorbents such as kaolinand bentonite clay, and i) lubricants such as talc, calcium stearate,magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate,and mixtures thereof. In the case of capsules, tablets and pills, thedosage form may also comprise buffering agents.

Solid compositions of a similar type may also be employed as fillers insoft, semi-solid and hard-filled gelatin capsules or liquid-filledcapsules using such excipients as lactose or milk sugar as well as highmolecular weight polyethylene glycols and the like.

The solid dosage forms of tablets, dragees, capsules, pills, andgranules can be prepared with coatings and shells such as entericcoatings and other coatings well known in the pharmaceutical formulatingart. They may optionally contain opacifying agents and can also be of acomposition that they release the active ingredient(s) only, orpreferentially, in a certain part of the intestinal tract, optionally,in a delayed manner. Examples of embedding compositions that can be usedinclude polymeric substances and waxes. Those embedding compositionscontaining a drug can be placed on medical devices, such as stents,grafts, catheters, and balloons.

The active compounds can also be in micro-encapsulated form, ifappropriate, with one or more of the above-mentioned excipients.

Liquid dosage forms for oral administration include pharmaceuticallyacceptable emulsions, solutions, suspensions, syrups and elixirs. Inaddition to the active compounds, the liquid dosage forms may containinert diluents commonly used in the art such as, for example, water orother solvents, solubilizing agents and emulsifiers such as ethylalcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzylalcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol,dimethyl formamide, oils (in particular, cottonseed, groundnut, corn,germ, olive, castor, and sesame oils), glycerol, tetrahydro-furfurylalcohol, polyethylene glycols and fatty acid esters of sorbitan, andmixtures thereof.

Besides inert diluents, the oral compositions can also include adjuvantssuch as wetting agents, emulsifying and suspending agents, sweetening,flavoring, and perfuming agents.

Suspensions, in addition to the active compounds, may contain suspendingagents such as, for example, ethoxylated isostearyl alcohols,polyoxyethylene sorbitol and sorbitan esters, microcrystallinecellulose, aluminum metahydroxide, bentonite, agaragar, and tragacanth,and mixtures thereof.

Topical administration includes administration to the skin or mucosa,including surfaces of the lung and eye. Compositions for topicaladministration, including those for inhalation, may be prepared as a drypowder which may be pressurized or non-pressurized. In non-pressurizedpowder compositions, the active ingredient in finely divided form may beused in admixture with a larger-sized pharmaceutically acceptable inertcarrier comprising particles having a size, for example, of up to 100micrometers in diameter. Suitable inert carriers include sugars such aslactose. Desirably, at least 95% by weight of the particles of theactive ingredient have an effective particle size in the range of 0.01to 10 micrometers. Compositions for topical use on the skin also includeointments, creams, lotions, and gels.

Alternatively, the composition may be pressurized and contain acompressed gas, such as nitrogen or a liquified gas propellant. Theliquified propellant medium and indeed the total composition ispreferably such that the active ingredient does not dissolve therein toany substantial extent. The pressurized composition may also contain asurface active agent. The surface active agent may be a liquid or solidnon-ionic surface active agent or may be a solid anionic surface activeagent. It is preferred to use the solid anionic surface active agent inthe form of a sodium salt.

A further form of topical administration is to the eye, as for thetreatment of immune-mediated conditions of the eye such as automimmuediseases, allergic or inflammatory conditions, and corneal transplants.The compound of the invention is delivered in a pharmaceuticallyacceptable ophthalmic vehicle, such that the compound is maintained incontact with the ocular surface for a sufficient time period to allowthe compound to penetrate the corneal and internal regions of the eye,as for example the anterior chamber, posterior chamber, vitreous body,aqueous humor, vitreous humor, cornea, iris/cilary, lens, choroid/retinaand sclera. The pharmaceutically acceptable ophthalmic vehicle may, forexample, be an ointment, vegetable oil or an encapsulating material.

Compositions for rectal or vaginal administration are preferablysuppositories or retention enemas which can be prepared by mixing thecompounds of this invention with suitable non-irritating excipients orcarriers such as cocoa butter, polyethylene glycol or a suppository waxwhich are solid at room temperature but liquid at body temperature andtherefore melt in the rectum or vaginal cavity and release the activecompound.

Compounds of the present invention can also be administered in the formof liposomes. As is known in the art, liposomes are generally derivedfrom phospholipids or other lipid substances. Liposomes are formed bymono- or multi-lamellar hydrated liquid crystals that are dispersed inan aqueous medium. Any non-toxic, physiologically acceptable andmetabolizable lipid capable of forming liposomes can be used. Thepresent compositions in liposome form can contain, in addition to acompound of the present invention, stabilizers, preservatives,excipients, and the like. The preferred lipids are the phospholipids andthe phosphatidyl cholines (lecithins), both natural and synthetic.Methods to form liposomes are known in the art. See, for example,Prescott, Ed., Methods in Cell Biology, Volume XIV, Academic Press, NewYork, N.Y. (1976), p. 33 et seq.

Compounds of the present invention may also be coadministered with oneor more immunosuppressant agents. The immunosuppressant agents withinthe scope of this invention include, but are not limited to, IMURAN®azathioprine sodium, brequinar sodium, SPANIDIN® gusperimustrihydrochloride (also known as deoxyspergualin), mizoribine (also knownas bredinin), CELLCEPT® mycophenolate mofetil, NEORAL® Cylosporin A(also marketed as different formulation of Cyclosporin A under thetrademark SANDIMMUNE®), PROGRAF® tacrolimus (also known as FK-506),sirolimus and RAPAMUNE®, leflunomide (also known as HWA-486),glucocorticoids, such as prednisolone and its derivatives, antibodytherapies such as orthoclone (OKT3) and Zenapax®, and antithymyocyteglobulins, such as thymoglobulins.

Example 3

The purpose of this example was to determine the effects of a rapamycinanalog on neointimal formation in porcine coronary arteries containingstents. This example illustrates that the rapamycin analog A-179578,when compounded and delivered from the Biocompatibles BiodiviYsio PCCoronary stent favorably affects neointimal hyperplasia and lumen sizein porcine coronary arteries. This finding suggests that such acombination may be of substantial clinical benefit if properly appliedin humans by limiting neointimal hyperplasia.

The agent A-179578 is a rapamycin analog. The study set forth in thisexample was designed to assess the ability of the rapamycin analogA-179578 to reduce neointimal hyperplasia in a porcine coronary stentmodel. Efficacy of A-179578 in this model would suggest its clinicalpotential for the limitation and treatment of coronary restenosis instents following percutaneous revascularization. The domestic swine wasused because this model appears to yield results comparable to otherinvestigations seeking to limit neointimal hyperplasia in humansubjects.

The example tested A-179578 eluted from coronary stents placed injuvenile farm pigs, and compared these results with control stents. Thecontrol stents had polymer alone covering its struts. This is important,for the polymer itself must not stimulate neointimal hyperplasia to asubstantial degree. As the eluted drug disappears, an inflammatoryresponse to the polymer could conceivably result in a late “catch-upphenomenon” where the restenosis process is not stopped, but insteadslowed. This phenomenon would result in restenosis at late dates inhuman subjects.

Stents were implanted in two blood vessels in each pig. Pigs used inthis model were generally 24 months old and weighed 30-40 kg. Twocoronary stents were thus implanted in each pig by visually assessing anormal stent:artery ratio of 1.1-1.2.

Beginning on the day of the procedure, pigs were given oral aspirin (325mg daily) and continued for the remainder of their course. Generalanesthesia was achieved by means of intramuscular injection followed byintravenous ketamine (30 mg/kg) and xylazine (3 mg/kg). Additionalmedication at the time of induction included atropine (1 mg) andflocillin (1 g) administered intramuscularly. During the stentingprocedure, an intraarterial bolus of 10,000 units of heparin wasadministered.

Arterial access was obtained by cutdown on the right external carotidand placement of an 8F sheath. After the procedure, the animals weremaintained on a normal diet without cholesterol or other specialsupplementation.

The BiodivYsio stent was used with nominal vessel target size of 3.0 mm.See FIG. 2. Two coronary arteries per pig were assigned at random todeployment of the stents. The stent was either a drug eluting stent(polymer plus drug stent) or a stent coated with a polymer only (polymeronly stent). The stents were delivered by means of standard guidecatheters and wires. The stent balloons were inflated to appropriatesizes for less than 30 seconds.

Each pig had one polymer only stent and one polymer plus drug stentplaced in separate coronary arteries, so that each pig would have onestent for drug and one for control.

A sample size of 20 pigs total was chosen to detect a projecteddifference in neointimal thickness of 0.2 mm with a standard deviationof 0.15 mm, at a power of 0.95 and beta 0.02.

Animals were euthanized at 28 days for histopathologic examination andquantification. Following removal of the heart from the perfusion pumpsystem, the left atrial appendage was removed for access to the proximalcoronary arteries. Coronary arterial segments with injuries weredissected free of the epicardium. Segments containing lesions wasisolated, thereby allowing sufficient tissue to contain uninvolved bloodvessel at either end. The foregoing segments, each roughly 2.5 cm inlength, were embedded and processed by means of standard plasticembedding techniques. The tissues were subsequently processed andstained with hematoxylin-eosin and elastic-van Gieson techniques.

Low and high power light microscopy were used to make lengthmeasurements in the plane of microscopic view by means of a calibratedreticle and a digital microscopy system connected to a computeremploying calibrated analysis software.

The severity of vessel injury and the neointimal response were measuredby calibrated digital microscopy. The importance of the integrity of theinternal elastic lamina is well-known to those skilled in the art. Ahistopathologic injury score in stented blood vessels has been validatedas being closely related to neointimal thickness. This score is relatedto depth of injury and is as follows:

Score Description of Injury 0 Internal elastic lamina intact;endothelium typically denuded, media compressed but not lacerated. 1Internal elastic lamina lacerated; media typically compressed but notlacerated. 2 Internal elastic lacerated; media visibly lacerated;external elastic lamina intact but compressed. 3 External elastic laminalacerated; typically large lacerations of media extending through theexternal elastic lamina; coil wires sometimes residing in adventitia.

This quantitative measurement of injury was assessed for all stent wiresof each stent section. The calibrated digital image was also used tomeasure at each stent wire site the neointimal thickness. Lumen area,area contained within the internal elastic lamina, and area within theexternal elastic lamina were also measured.

At each stent wire site for a given section, the neointimal thicknesswas averaged to obtain a mean injury score for each section. Themeasurement of neointimal thickness was made to the abluminal side ofthe stent wire, because the neointimal in all cases includes thisthickness.

The mid-stent segment was used for measurement, analysis, andcomparison. Data were also recorded (and included in the data section ofthis report) for proximal and distal segments.

The data analysis methods for this study did not need to take intoaccount variable arterial injury across treatment/control groups,because mild to moderate injury is sensitive enough to detect treatmentdifferences. Paired t-testing was performed to compare variables acrossthe polymer only stents (control group) and polymer plus drug stents(treatment group). No animal died in this study before scheduledtimepoints.

Table 3 shows the pigs and arteries used. In Table 3, LCX means thecircumflex branch of the left coronary artery, LAD means the leftanterior descending coronary artery, and RCA means the right coronaryartery.

TABLE 3 Pigs and Vessels Used 1 2000-G-693 RCA - Control 2000-G-693LCX - Test 2 2000-G-698 RCA - Test 2000-G-698 LAD - Control 3 2000-G-702RCA - Test 2000-G-702 LAD - Control 4 2000-G-709 RCA - Control2000-G-709 LAD - Test 5 2000-G-306 RCA - Control 2000-G-306 LAD - Test2000-G-306 *LCX - Test 6 2000-G-672 RCA - Test 2000-6-672 LAD - Control7 2000-G-712 RCA - Control 2000-G-712 LCX - Test 8 2000-G-735 RCA -Control 2000-G-735 LAD - Test 9 2000-G-736 RCA - Control 2000-G-736LCX - Test 10 2000-G-740 RCA - Test 2000-G-740 LAD - Control 112000-G-742 LAD - Test 2000-G-742 OM (LCX) - Control 12 2000-G-744 RCA -Test 2000-G-744 LAD - Control 13 2000-G-748 RCA - Test 2000-G-748 LAD -Control 14 2000-G-749 RCA - Control 2000-G-749 LCX - Test 15 2000-G-753RCA - Control 2000-G-753 LAD - Test 16 2000-G-754 RCA - Test 2000-G-754LCX - Control 17 2000-G-755 RCA - Control 2000-G-755 LAD - Test 182000-G-756 RCA - Test 2000-G-756 LAD - Control 19 2000-G-757 LAD -Control 2000-G-757 LCX - Test 20 2000-G-760 LAD - Test 2000-6-760 LCX -Control

Table 4 shows the summary results for all data for mean injury andneointimal thickness for each stent, including proximal, mid, and distalsegments. Table 4 also shows lumen size, percent stenosis, and arterysize as measured by the internal elastic laminae (IEL) and externalelastic laminae (EEL).

TABLE 4 Summary: All Measures (Distal, Mid, Proximal) dist mean %neointimal ID prox ref ref lumen IEL EEL injury stenosis area NITControl Distal Mean 4.46 3.96 4.88 7.66 9.00 0.22 36.10 2.79 0.41 SD1.20 1.16 1.30 1.15 1.10 0.26 15.41 1.29 0.17 Control Mid Mean 4.46 3.964.94 7.71 9.08 0.08 36.23 2.77 0.38 SD 1.20 1.16 1.44 1.07 1.15 0.1414.93 1.20 0.16 Control Proximal Mean 4.46 3.96 5.11 7.89 9.30 0.1535.35 2.78 0.38 SD 1.20 1.16 1.38 1.33 1.42 0.22 11.94 1.04 0.12 TestDistal Mean 4.26 3.41 6.04 7.70 9.01 0.26 22.35 1.66 0.25 SD 1.26 0.961.55 1.49 1.47 0.43 8.58 0.58 0.06 Test Mid Mean 4.26 3.41 6.35 7.758.98 0.04 18.71 1.41 0.22 SD 1.26 0.96 1.29 1.18 1.31 0.07 5.68 0.330.05 Test Proximal Mean 2.56 2.15 3.31 4.06 4.66 0.19 16.79 1.29 0.18 SD1.66 1.37 2.39 3.48 4.15 0.13 9.97 0.80 0.12

There was no statistically significant difference for neointimal area orthickness across proximal, mid, or distal segments within the test group(polymer plus drug stents) or control groups (polymer only stents). Thisobservation is quite consistent with prior studies, and thus allows useof only the mid segment for statistical comparison of test devices(polymer plus drug stents) vs. control devices (polymer only stents).

Table 5 shows the statistical t-test comparisons across test groups andcontrol groups. There was a statistically significant difference inneointimal thickness, neointimal area, lumen size, and percent lumenstenosis, the drug eluting stent being clearly favored. Conversely,there were no statistically significant differences between the testgroup (polymer plus drug stents) and the control group (polymer onlystents) for mean injury score, external elastic laminae, or internalelastic laminae areas.

TABLE 5 Statistical Comparison of Test vs. Control Parameters:Mid-Section Data t-test Statistics Std Lower Upper Parameter Differencet-test DF Error 95% 95% p Lumen −1.17 −2.28 38 0.52 −2.21 −0.13 0.029IEL 0.03 0.088 38 0.36 −0.71 0.78 0.93 EEL 0.2 0.499 38 0.39 −0.599 0.990.62 NI 0.18 5.153 38 0.034 0.106 0.244 <0.0001 Thickness NI Area 1.213.62 38 0.33 0.53 1.88 0.0008 Mean 0.038 1.137 38 0.033 −0.02 0.106 0.26Injury % Stenosis 14.54 2.97 38 4.9 4.61 24.47 0.005

The reference arteries proximal and distal to the stented segments wereobserved, and quantitated. These vessels appeared normal in all cases,uninjured in both the control group (polymer only stents) and the testgroup (polymer plus drug stents). See FIGS. 3A and 3B. The data belowshow there were no statistically significant differences in size betweenthe stents in the control group and the stents in the test group.

Proximal Reference Distal Reference Diameter (mm) Diameter (mm) Control(mean ± SD) 4.46 ± 1.20 3.96 ± 1.16 Test (mean ± SD) 4.26 ± 1.26 3.41 ±0.96

The data suggest that statistically significant differences exist, andthese differences favor the stent that elutes A-179578. The stent ofthis invention results in lower neointimal area, lower neointimalthickness, and greater lumen area. There were no significant differenceswithin the test group (polymer plus drug stents) and the control group(polymer only stents) for neointimal or injury parameters. There were nosignificant differences in artery sizes (including the stent) for thecontrol group compared to the test group. These latter findings suggestno significant difference in the arterial remodeling characteristics ofthe polymeric coating containing the drug.

At most, mild inflammation was found on both the polymer plus drug stentand the polymer only stent. This finding suggests that the polymerexhibits satisfactory biocompatibility, even without drug loading. Otherstudies show that when drug has completely gone from the polymer, thepolymer itself creates enough inflammation to cause neointima. Thisphenomenon may be responsible for the late catch-up phenomenon ofclinical late restenosis. Because the polymer in this example did notcause inflammation in the coronary arteries, late problems related tothe polymer after the drug is exhausted are unlikely.

In conclusion, a stent containing the compound A-179578 with a polymershowed a reduction in neointimal hyperplasia in the porcine model whenplaced in a coronary artery.

Example 4

The purpose of this example is to determine the rate of release of theA-179578 drug from 316L Electropolished Stainless Steel Coupons coatedwith a biocompatible polymer containing phosphorylcholine side groups.

Rubber septa from lids from HPLC vials were removed from the vials andplaced into glass vials so that the “Teflon” side faced up. These septaserved as supports for the test samples. The test samples were 316Lstainless steel coupons that had been previously coated with abiocompatible polymer containing phosphorylcholine side groups (PCpolymer). Coronary stents are commonly made of 316L stainless steel andcan be coated with the PC polymer to provide a depot site for loadingdrugs. The coated coupons, which serve to simulate stents, were placedonto the septa. By using a glass Hamilton syringe, a solution ofA-179578 and ethanol (10 ul) was applied to the surface of each coupon.The solution contained A-179578 (30.6 mg) dissolved in 100% ethanol (3.0ml). The syringe was cleaned with ethanol between each application. Thecap to the glass vial was placed on the vial loosely, thereby assuringproper ventilation. The coupon was allowed to dry for a minimum of 1.5hours. Twelve (12) coupons were loaded in this way—six being used todetermine the average amount of drug loaded onto the device and sixbeing used to measure the time needed to release the drug from thedevices.

To determine the total amount of ABT-578 loaded onto a coupon, a couponwas removed from the vial and placed into 50/50 acetonitrile/0.01Mphosphate buffer (pH 6.0, 5.0 ml). The coupon was placed onto a 5210Branson sonicator for one hour. The coupon was then removed from thesolution, and the solution was assayed by HPLC.

The time release studies were performed by immersing and removing theindividual coupons from fresh aliquots (10.0 ml) of 0.01 M phosphatebuffer at a pH of 6.0 at each of the following time intervals—5, 15, 30and 60 minutes. For the remaining time points of 120, 180, 240, 300, and360 minutes, volumes of 5.0 ml of buffer were used. To facilitate mixingduring the drug release phase, the samples were placed onto an Eberbachshaker set at low speed. All solution aliquots were assayed by HPLCafter the testing of the last sample was completed.

The HPLC analysis was performed with a Hewlett Packard series 1100instrument having the following settings:

Injection Volume = 100 ul Acquisition Time = 40 minutes Flow Rate = 1.0ml/min Column Temperature = 40° C. Wavelength = 278 nm Mobile Phase =65% acetonitrile/35% water Column = YMC ODS-A S5 μm, 4.6 × 250 mm PartNo. A12052546WT

The results from the above experiment showed the following release data:

TABLE 6 Time Percent Standard (min.) Release Deviation 0.00 0.00 0.005.00 1.87 1.12 15.00 2.97 1.47 30.00 3.24 1.28 60.00 3.29 1.29 120.003.92 1.28 180.00 4.36 1.33 240.00 4.37 1.35 300.00 6.34 2.07 360.00 7.881.01

Example 5

The purpose of this example was to determine the loading and release ofA-179578 from 15 mm BiodivYsio drug delivery stents.

To load the stents with drug, a solution of A-179578 in ethanol at aconcentration of 50 mg/ml was prepared and dispensed into twelve vials.Twelve individual polymer-coated stents were placed on fixtures designedto hold the stent in a vertical position and the stents were immersedvertically in the drug solution for five minutes. The stents andfixtures were removed from the vials and excess drug solution wasblotted away by contacting the stents with an absorbant material. Thestents were then allowed to dry in air for 30 minutes in an invertedvertical position.

The stents were removed from the fixtures, and each stent was placedinto 50/50 acetonitrile/phosphate buffer (pH 5.1, 2.0 ml) and sonicatedfor one hour. The stents were removed from the solution and solutionswere assayed for concentration of drug, which allowed calculation of theamount of drug originally on the stents. This method was independentlyshown to remove at least 95% of the drug from the stent coating. Onaverage, the stents contained 60 micrograms of drug ±20 micrograms.

The drug-loaded stents were placed on the fixtures and placed into 0.01M phosphate buffer (pH=6.0, 1.9 ml) in individual vials. These sampleswere placed onto an Eberbach shaker set at low speed to provideback-and-forth agitation. To avoid approaching drug saturation in thebuffer, the stents were transferred periodically to fresh buffer vialsat the following points: 15, 30, 45, 60, 120, 135, 150, 165, 180, 240,and 390 minutes. The dissolution buffer vials were assayed by HPLC forthe drug concentration at the end of the drug release period studied.The data, represented as % cumulative release of the drug as a functionof time, is shown in tabular form below:

TABLE 7 Time (min.) % Cumulative Release of Drug 15 0.3 30 1.1 45 2.1 603.2 120 4.3 135 5.9 150 6.3 165 6.8 180 7.4 240 10.8 390 13.2

Example 6

The purpose of this example was to evaluate the safety and efficacy ofdifferent drug dosages on neointima formation. Drug was delivered fromthe BiodivYsio OC stent (15 mm) coated with A-179578. In-stent neointimaformation was measured at four time intervals—3 days, 1 month, and 3months—in the coronary arteries of adult miniature swine. Forty (40)animals were studied at each time interval (10 animals per dose). Eachanimal received one drug-coated stent and one control stent. The controlstent contained no drug. Table 8 shows the dosing scheme for swineefficacy study.

TABLE 8 Dose group Dose group Dose group Dose group 1 (μg) 2 (μg) 3 (μg)4 (μg) A-179578 per 15 45 150 400 stent A-179578 per 1 3 10 27 mm ofstent

Potential local tissue toxicity was assessed at all time intervals byexamining histopathologic changes in the stented region, adjacentcoronary segments, peri-vascular tissue, and subserved myocardium. Themortality, angiographic implant and restudy data, histomorphometry data,and stent site histopathology were studied

Three-Day Group

Histopathology in combination with scanning electron microscopy providedinformation regarding the short-term response to the implanted stent.The responses were similar in the control group and all dose groups, andthe responses involved compression of the tunica media withoutremarkable necrosis, an accumulation of thrombus and inflammatory cellsmostly localized to the stent struts, and early evidence of endothelialrecovery and smooth muscle cell invasion of the thin mural thrombi.There were no extensive thrombi or remarkable intramural hemorrhages.The adventitia in some samples displayed either focal or diffuseinflammatory infiltrates, and occasionally there was plugging orcongestion of the vasa vasora. There was no evidence of medial necrosisin any sample.

Scanning electron microscopy showed similar appearance of the luminalsurface three days after the implant of the coronary stent in all dosegroups. The shape of the stent was clearly embedded in a thin layer oftissue. The endothelium was intact between the struts and even over thestruts; a confluent or nearly confluent layer of endothelial-like cellshad covered the luminal surface. There were scattered adherentplatelets, platelet microthrombi, and leukocytes over the stents and onthe intact remnant endothelium in the inter-strut spaces. In arterieswith more severe stent-induced vessel damage, there were moresubstantial mural thrombi, but the extent of endothelial recovery overthe stent struts did not appear retarded, regardless of the dosage ofA-179578.

One-Month Group

The histomorphometry data for the one-month series indicated asignificant inhibitory effect of locally eluted A-179578 on neointimaformation in stented coronary arteries of swine. Intima area normalizedto injury score was significantly decreased for dose groups 3 and 4 (10and 27 ug/mm) as compared with the control; there were also trends fordecreases in absolute intima area and intima thickness for both dosegroups 3 and 4 as compared with the control, and a tendency towardsdecreased histologic % stenosis for dose group 3 as compared with thecontrol.

The control stents displayed morphology typical of stents implanted incoronary arteries of Yucatan miniature swine at one month. The tunicamedia was compressed or thinned without necrosis subjacent to profilesof stent struts; there were only occasional inflammatory infiltrates;and the neointima ranged in size from relatively thin to moderatelythin, and were composed of spindle-shaped and stellate cells in anabundant extracellular matrix, with only rare small foci of fibrinoidmaterial around the profiles of the stent struts. The drug-coated stentsshowed similar compression of the tunica media without any substantialnecrosis at any dose; like control devices, there was littleinflammation present. The neointima was notably thinner in dose groups 3and 4, in some cases being composed of only a few layers of cells. Inall dose groups, there were substantial numbers of samples in whichmoderately sized fibrinoid deposits and inspisated thrombi were observedin the deep neointima. These were usually associated with the stentstruts but sometimes extended between strut profiles. However, in nocase was there exposure of thrombus on the luminal surface, as thedeposits were encapsulated within fibrocellular tissue and covered witha flattened layer of periluminal endothelial-like cells.

Scanning electron microscopy confirmed that a confluent layer ofendothelial or endothelial-like cells covered the entire stentedsurface, and there was no difference between drug-coated stents andcontrol stents in terms of adherence of blood elements; leukocytes werepresent in approximately equal numbers in all groups. These findingsdemonstrate that while A-179578 was associated with decreased neointimaformation and persistent mural thrombi, sufficient vessel wall healingin response to stent injury had occurred within one month after thestent had been implanted. This vessel wall healing had rendered theluminal surface non-reactive for platelet adhesion and thrombusformation, and minimally reactive for leukocyte adherence. Additionally,there was no evidence of vessel wall toxicity even at the highest dose(27 μg/mm), as there was no medial necrosis or stent malapposition.

Three-Month Group

There were no significant differences between the dose groups for anyhistomorphometric parameters of stented coronary arterial dimension inthe three-month period of the study. However, there were weak trends fordecreases in the two primary variables describing neointimaformation—the cross-sectional area and the % area stenosis of the lumen.

The histopathologic appearance of the control stents in the swinecoronary artery samples at three months after the implant appearedsimilar to that of the controls from the one-month group, and similar tothose of all the groups in the three-month period. All samples showedfibrocellular neointima formation with mostly spindle-shaped smoothmuscle-like cells in the neointima and a confluent squamous periluminalcell layer. There were no intramural hemorrhages or persistent fibrinoiddeposits in the neointima; however some samples, particularly those withthicker neointima, showed evidence of prior thrombus accumulation andsubsequent organization in the form of neovascularization in theneointima. On occasion, samples showed evidence of moderate to severeinflammatory reactions localized to the stent struts, associated withdestruction of the tunica media architecture. These were most oftenassociated with thicker neointima as well. However, these were few innumber and were found in the control group as well as in the drug-coatedstent groups. It is presumed that these represented eitheranimal-specific generalized reactions to the implanted stent, evidenceof contamination of the stent, or some combination of these two factors,and is commonly found at an incidence of about 10-15% in the studies ofstent implants in swine coronary arteries. There was no evidence ofnecrosis of the tunica media or separation of the media from the stentin any sample. The adventitia of most three-month implants appeared tohave somewhat greater neovascularization than did the one-monthimplants, but this did not appear related to control or test stentgroup. Scanning electron microscopy demonstrated confluent endotheliumwith rare adherent blood cells in the control group and all dose groups.

CONCLUSIONS

The stent coated with A-179578 reduced in-stent neointima formation inswine coronary arteries and provided clear evidence of a biologic drugeffect (unresorbed thrombus/fibrin deposits of neointima) at one month.There was a weak tendency for the stent coated with A-179578 to show apersistent inhibitory effect at the longer-term time interval of threemonths. There was no local coronary arterial wall toxicity in the formof medial necrosis or stent malapposition associated with any dosegroup, including the highest dose of approximately 27 μg/mm stent lengthat any time interval examined. All stents were well incorporated intothe tissue, and there was evicence of stable healing responses in theform of fibrocellular neointimal incorporation and endothelial coverageat the one-month interval and at the three-month interval. The trendtowards a sustained inhibitory effect at three months after the stentwas implanted in this animal is surprising and provides evidence forpotentially persistent effects in preventing clinical restenosisresulting from implanted stents.

It is understood that the foregoing detailed description andaccompanying examples are merely illustrative and are not to be taken aslimitations upon the scope of the invention, which is defined solely bythe appended claims and their equivalents. Various changes andmodifications to the disclosed embodiments will be apparent to thoseskilled in the art. Such changes and modifications, including withoutlimitation those relating to the chemical structures, substituents,derivatives, intermediates, syntheses, formulations and/or methods ofuse of the invention, may be made without departing from the spirit andscope thereof.

What is claimed is:
 1. A medical device comprising a supportingstructure having a coating on the surface thereof, wherein the coatingcomprises the therapeutic substance

and further comprises (1) a biocompatible polymer containing phosphorylcholine side groups (PC polymer); (2) a polyvinylpyrrolidone mixed witha polyester, a polyvinyl alcohol, or a polycarboxylic acid; (3) anacrylic copolymer mixed with a polyolefin, a polyester, or a polyvinylalcohol; (4) a polyvinylpyrrolidone copolymer; or (5) a polyestercopolymer; and wherein the coating serves as a controlled releasevehicle for the therapeutic substance.
 2. The medical device of claim 1,wherein the coating comprises the biocompatible polymer containingphosphoryl choline side groups (PC polymer).
 3. The medical device ofclaim 1, wherein the coating comprises the polyvinylpyrrolidone mixedwith a polyester, a polyvinyl alcohol, or a polycarboxylic acid.
 4. Themedical device of claim 1, wherein the coating comprises the acryliccopolymer mixed with a polyolefin, a polyester, or a polyvinyl alcohol.5. The medical device of claim 4, wherein the acrylic copolymer ishydrophobic.
 6. The medical device of claim 4, wherein the acryliccopolymer is hydrophilic.
 7. The medical device of claim 1, wherein thecoating comprises the polyvinylpyrrolidone copolymer.
 8. The medicaldevice of claim 7, wherein the polyvinylpyrrolidone copolymer ishydrophilic.
 9. The medical device of claim 1, wherein the coatingcomprises the polyester copolymer.
 10. The medical device of claim 9,wherein the polyester copolymer is hydrophobic.
 11. The medical deviceof claim 9, wherein the polyester copolymer is hydrophilic.
 12. Themedical device of claim 1, wherein the medical device is stent and saidcoating contains the therapeutic substance in an amount of 0.067 μg permm stent to 8 μg per mm stent.
 13. The medical device of claim 1,wherein said supporting structure is selected from the group consistingof coronary stents, peripheral stents, catheters, arterio-venous grafts,by-pass grafts, and drug delivery balloons used in the vasculature.